He said he will speed up development work initiated by him earlier. The 66-year-old Janata Dal-United leader was administered the oath of office as the 24th Chief Minister of Bihar by Governor Keshri Nath Tripathi.

Along with Nitish Kumar, 22 Ministers also took oath at a simple ceremony at Raj Bhavan.

Kumar got back the reins of Bihar after he took oath as Chief Minister, capping a long political drama which ended in an anti-climax with rebel JD(U) leader Jitan Ram Manjhi resigning shortly before the floor test on Friday.

Kumar has been asked to prove his majority on the floor of Assembly in three weeks time before March 16.

His government would take a decision to call the new budget session and fix a date for the Governor's speech in the joint session, the chief minister-designate said.

A series of high-voltage political events that saw Kumar back to power after nine months began with the resignation of Manjhi who sensed the clear lack of number to pass the crucial floor test in the Assembly.

This is the fourth time that Kumar took on the mantle of Bihar Chief Minister.

His first stint had lasted merely a week from March 3 to March 10 in 2000 and the second from November 24, 2005 to November 24, 2010.

The third term was from November 26, 2010 till he resigned from his post on May 17, 2014 in the wake of the debacle of JD(U) in the general election. He had then handpicked Manjhi to succeed him but the mentor and the protege later parted ways.